Before going into detail with this answer, you need to know two terms:

  1. A pixel, in the maps’ context, means an actual area in nature that is approximately 30 m ✕ 30 m = 900 m2. Single.Earth uses this area for estimations, and its size is dictated by the info from the satellites. In our maps, the whole world has been divided into pixels of this size.

  2. Canopy cover density means the proportion of the forest floor that is covered by the tree canopy as looked from above the forest, as to how an overflying satellite would see it. The canopy cover density is measured in percentages.

So, why doesn’t the CO2 absorption map’s overlay match the actual forest cover in your forest?

The map overlay depends on some technical aspects, and the existing canopy cover is not accounted for as a forest if any of the following three statements is true about (parts of) the forest in question:

  • The canopy cover density in 2000 was below 30%. According to the forest definition Single.Earth uses, we do not consider pixels with a canopy cover density below 30% a forest. Regional differences in the percentage due to forest or ecosystem type can apply.

  • Some parts of the forest are too young to be eligible. In Single.Earth, we do not include areas to the overlay that have either suffered losses (due to, e.g., fires, clearcutting, etc.) or established the suitable height (≥ 5 m) after the year 2000.

  • The accuracy of the canopy vs non-canopy classification is somewhat reduced at forest boundaries as the forest’s canopy density can vary in these areas.

If these three statements fail to describe the mismatching parts of the overlay on your land, it is possible to have our specialists look at the data. Our team might ask you to provide additional information about the forest.

More details are available on our science whitepaper.

🛠️ If you notice an inconsistency in the CO2 map overlay, we would appreciate it if you reported it via this form.

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